I'm not sure if this might help you and it certainly isn't going to be found in one place, at least I don't know of anything, but if you use an iphone there is a good app called "posing app" that has quite a few poses you might find helpful.

I always feel funny paying for apps... I did download a couple of free ones though, thanks for the heads up.

I personally scour 500px and Flickr, also magazines have tons of different types of poses you can find.

I love 500px! Good idea!

Of course there are a ton of different ways one can poses someone, if you look around the most successful poses are the ones being used most often, time and time again.

What changes though is the lighting, the props and the location. Since you have a family member willing to pose for you, experiment as much as you can.

Sign up for Model Mayhem as well. Maybe you could benefit with finding a couple of models willing to do Time For Print (TFP) who have previous experience and take note how they pose.